Traditionally, telephone subscribers received local service (i.e., dial tone) from a Local Exchange Carrier (LEC), typically operated by a Regional Bell Operating Company (RBOC) or an independent telephone carrier. In many geographic areas, telephone subscribers may now receive local telephone service from their provider of cable television services.
In order to attract subscribers, cable television service providers must offer telephony service comparable to that currently available from a LEC. In other words, the cable telephony service available from the cable television provider should offer a comparable array of features, such as Caller Identification, Call Waiting and Voice Mail, to name a few, that are available to subscribers of traditional local telephony service. In practice, LEC-based subscribers receive special-featured local telephony service via a central office switch programmed to provide such features, such as a Lucent 5ESS® switch manufactured by Lucent Inc, Murray Hill, N.J. Some cable television service providers also employ traditional central office telephone switches on their own premises to offer analog cable telephony with comparable features.
Currently, there is a trend by cable television service providers to offer Voice-over-Internet Protocol (VoIP) telephony service via the provider's Hybrid Fiber-Coax (HFC) network. In order to provide a full array of features to subscribers of these HFC VoIP telephony services, cable television service providers have had to provide the necessary call processing features in their own networks usually by way of an IP-Soft Switch, often at significant expense.
Thus, there is a need for a technique that affords a cable television service provider the ability to offer fully-featured VoIP telephony service yet avoids the need to perform the requisite call processing in the cable television service provider's own network.